Portion of a display screen with a user interface



FIG. 1 is a front view of a portion of a display screen with a userinterface showing a first embodiment of our new design; and,

FIG. 2 is a front view of a portion of a display screen with a userinterface showing a second embodiment of our new design.

The broken line showing of the portion of the display screen is includedfor the purpose of illustrating the unclaimed environment of the userinterface and forms no part of the claimed design. The broken linesdefining the five unclaimed rectangular regions represent boundary linesand form no part of the claimed design.

The ornamental design for a portion of a display screen with a user interface, as shown and described. 